A geographical division of North America developed to enhance the operation of the Regional Plan. In 2006, a major reorganization of the of the regions was completed, resulting in 14 large regions identified by geographical location. Each region contains a number of chapters and colonies and is serviced by a number of Regional Counselors.

The regions in Theta Chi Fraternity are Northeast, Mid-Atlantic, Atlantic, Ohio Valley, Carolinas, Southeast, Great Lakes, Midwest, Upper Plains, Lower Plains, Southwest, Southern California-Arizona, Northern California, and the Northwest.